Automobile inside tire.



G. A. LE DOUX.

AUTOMOBILE INSIDE TIRE.

APPLICATION FILED AUG.I3. I918.

1,300,980, Patented Apr. 15, 1919.

A TTORNE YS.

GEORGE A. LE DOUX, OF SAN FRANCISCO, CALIFORNIA.

AUTOMOBILE INSIDE TIRE.

Speci'fication of Letters Patent.

Patented Apr. 15, 1919.

Application fi1ed August 13, 1918. Serial No. 249,605.

T0 aol w/rom 2'25 may concern:

Be it known that I, GEORGE A. LE DOUX,-

new and useful Improvements in Automobile Inside Tires, of which the following is a specification.

My invention relates to the class of inside tires or shields which lie between the outer casing and the pneumatic tube 01 the tireassemblage of automobile wheels. Heretofore these inside tires have commonly been made of worn outer casings stripped down to a few layers, or have been specially prepared as annular shoes or linings. But in their manufacture and use no attention is paid to the relative circumferences of the contacting surfaces of inside tire and casing other than that which is necessary to efiect the entrance of the former into the latter and its fit therein with reasonable closeness.

Accordingly the inside tire may be, purely incidentally, of exterior circumference less than the interior circumference of the cas.- ing, approxiflrately the sarne circumference or larger. In the former cases cementing of the adjacent surfaces is -practised to prevent relative movement with its well known delcterious effects; and in the last case, reliance is placed, to avoid creeping, upon the close but uncemented contactof the surfaces due to oversize of the inside tire, which latter condition, that is, oversize, is however, more or less purel accidental, and in any case, whcther accidental or predetermined is slight, because it has heretofore quite naturally been considered that excessive oversizc is inconsistent with a fit.

I have found in practice that none of these conditions, namely, undersize or approximate same size with cernent, nor slight over size without cernent is suflicient to prevent creeping, and this has led meto the discovery that an oversize of the inside-tire With the addition of cernent between the adjacent surfaces of said tire and the casing is not only a solution of the creeping problem, but that when the oversize is pronounced or relatively large it is also of great advantage in materially.widening the range of utility of any given inside-tire in its application to casings b0th new and old. By this I mean that a given inside-tire of relatively large oversize may be applied to either a neW casin g which is unstretchod, or to an old cas ing which is stretched; and with the addition cf cernent, may be fitted, with no tendency or chance to creep.

This, therefore, is the object of my pres, ent invention, and -to this end my invention may be stated briefly and essentially to consist in a pneumatic tire assemblage comprising an outer casing, an inner tube, an inside elastic tire lying between the outer casing and the inner tube, and having a normal outside diarneter greater than the inside diameter of the casing, and cementitious material uniting the djacent surfaces of the outer casing and the inside tire.

My.invention also consists in novel details of construction which I shall hereinafter fully describe, by reference to the accompanying drawings in which:

Figure 1 is a fragmentary perspective view, broken and partly in section of my tire assemblage.

Fig. 2 is a cross-section of my said tire assemblage, on the line 22 of Fig. 1.

1 is the outer casing having the beads 2. 3 is a flap for protecting the inner tube 4 at the wheel rim. 5 is the inside-tire cf substantially uniform thickness lying between and throughout the entire circumference of the casing and tube. 6 indicates a layer of cernent, herein exaggerated for the sake of clearriess, said layer uniting the adjacent surfaces of the inside tire and the outer casing. y

The inside tire 5 may be made of any suitable material and by any suitable method. Its only esscntial in this respect is that it shall have suflicient elasticity to enable it to be compressed to scat i-tself within the outer casing. I have accordingly illustrated it in Fig. 2 as composed of circumferentially su perimposed layers cf fabric 5 and inter- Vening layers 5 of rubber.

This inside tire has a normal or uncornpressed outside diameter and outside circumference greater than the inside diameter and inside circumference of the casing, as is illustrated by its exposed slack portion in Fig. 1. The elastic nature of the inside tire enables it, notwithstanding its oversize, to be com.pressed to its scat smoothly, in the outer casing. When so seated, the cemcntitious material 6 having previously been applied unites the adjacent surfaces, and the double seeurity against creeping afiorded by the tight fit of the inside tire due to its over size. and the cement is complete,

In practice, I make the oversize of the inside-tire qu'rte pronounced or relatively large. By this I gain not only the maximum tightness of fit under normal conditions as with new casings but also provide for its application to old tires, because the excessive oversize gives a sufiiciently Wide range to adapt the inside-tire to the possibly stretched condition of theold tires, with the combined effects of oversize and cemen titions adhesion still present. As a further insurance against creeping, I secure or form With one edge of the inside tire 5, a holding fiap 7 which extends outwardly over the bead 2 of the casing, and is clamped between said bead and the wheel rim.

The fiap 3 may be the usual protection flap, but I prefer to secure it to or form it With one edge of the inside tire as shown. T 1115 flap is sufiiciently thick to prevent it from wrinkling or buckling S0 as not to pinch the inner tube. lt tapers to a thin edge and the air valve hole in,it should be larger than usual so that the inner tire to which it is secured can expand and contact without pressure on the air valve stem.

' daim:

In combination With the outer casing and the inner tube of a pneumatic tire; an elastic inside tire lying between and throughout the entire circumferene of the oasing and the tube, said inside-tire having when uncompressed an outside diameter greater than the inside diameter of the casing; and cementitions material uniting the adjacent surfaces of the inside-tire and the outer casing.

In testimony whereof I[ have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE A. LE DOUX.

Witneeses:

WM. F. BOOTH, D. B. RICHARDS. 

